Angle-Resolved Enhancement of Rh800 Dye Photoluminescence Using Plasmonic Metal Gratings

In this study, metal gratings were used to resonantly control and enhance the photoluminescence (PL) of Rh800 dye molecules at different angles by designing plasmon resonance modes that align with the excitation wavelengths. The experimental results show that when the plasmon resonance mode closely matched the excitation wavelength, the PL increased by a factor of 22. When the resonant position was not closely aligned with the excitation wavelength, PL enhancement remained significant, up to 14 times. Furthermore, even in the absence of a grating and with only a thin-film structure, the PL enhancement can still reach up to 5 times. Numerical simulations were also performed to analyze the effects of resonance mode, field distribution, and local field enhancement on the characteristics of the grating structure. The simulated results showed good agreement with experimental observations. The proposed structures offer greater flexibility for resonantly manipulating and enhancing PL across a wide range of applications. It offers significant opportunities in sensing, imaging, optoelectronics, energy conversion, catalysis, and biomedical diagnostics, such as disease biomarker detection.